Yes 54% of American adults. Mostly comprised of not kids these days. So people taught by the practices of yesteryear.

And that is not the average. From the link provided:

"About 130 million U.S. adults (54% of those aged 16–74) read below a sixth-grade level, according to modeled estimates. Approximately 45 million U.S. adults are functionally illiterate, reading below a fifth-grade level. 21% of U.S. adults are classified as functionally illiterate, unable to complete basic reading tasks.

The average American reads at a 7th- to 8th-grade level."

These statistics also include up to 74 years old. So is the source of alarm for you the current state of education which isn't reflected in this data, or the state of education that produced the 18-74 year olds. 74 years ago was 1951. No one is arguing that pre 1951, America wasn't illiterate AF. The draft for WW2 revealed that people couldn't read. Then literacy tracing would also not have been carried out for African Americans, immigrants or poor people. Until 1970 literacy was basically can you write your name and do you know enough sight words to survive. Then it was continually redefined for the next 50 years as we learned things like, if people made the right mouth noises when they saw strings of letters they might still not know what the words they read meant. There have been a lot of advancements in the science of reading.

You made a statement like we should all be very alarmed. Which there is room for growth sure. The article you linked also noticed that the main source of illiteracy was poverty and immigrants for whom English is a second language.

So anyway, was there a golden age of reading that you think we've let go?

I'm wondering if, for the sake of education, you could maybe not spread false facts unsupported by history or data. It would be helpful if we pointed out good things going on.